A VTOL aerial vehicle can be used for a number of applications. The conditions under which a VTOL aerial vehicle must land may be variable. For example, the landing surface may be moving at the time the VTOL aerial vehicle is landing. For VTOL aerial vehicles that are operating at sea it is quit difficult to safely land on the deck of a ship due to constant sway, roll, pitch and yaw of a ship at sea. It can also be quite difficult to safely land on the deck of an offshore platform such as an oil drilling platform or on solid ground in zones exposed for violent winds. Therefore the VTOL aerial vehicle needs to be locked during landing in order to prevent sliding or toppling of the VTOL aerial vehicle. Sliding or toppling of a VTOL aerial vehicle can result in damage to or even loss of the VTOL aerial vehicle.
VTOL aerial vehicles often have a harpoon and grid securing system for securing the VTOL aerial vehicle to a platform during landing. These systems comprise a grid mounted on the landing and take-off platform. The harpoon is mounted underneath the VTOL aerial vehicle and substantially comprises a retractable arm and, at the end of the arm, a head for catching in the grid. During landing the harpoon descends vertically towards the grid and then goes down into the grid and thereby locks the VTOL aerial vehicle to the platform. Harpoon and grid securing system comprise, apart from a harpoon, an electric/pneumatic unit, hoses and mounting devices. Therefore the harpoon and grid securing system is quite large, heavy and bulky. In addition, there is no or little room for both a harpoon and grid securing system and a camera/radar sensor.
Another example of a known anchoring system for an unmanned aerial vehicle (UAV) landing vertical onto a ship is shown in document US-A1-2004256519. An aerial vehicle recovery system includes a landing pad secured or securable to a supporting surface. The landing pad has an upwardly facing capture surface having a passive retaining medium thereon. The aerial vehicle to be recovered includes one or more shoes affixed to a lower portion of the aerial vehicle. The shoes have a complementary passive retaining medium thereon configured to mate or interlock with or adhere to or otherwise interface with the retaining medium of the capture surface on the landing pad. The retaining medium on the landing pad and the complementary retaining medium on the aerial vehicle together form a passive retaining system that retains the vehicle on the landing pad upon the exertion of sufficient compressive force by the vehicle on the capture surface. The aerial vehicle recovery system can be used in conjunction with a variety of supporting surfaces, such as a ship's deck, an offshore platform, a truck grid, or the ground.
The system that is disclosed in the document US-A1-2004256519 has several drawbacks. One drawback is that the retaining medium on the aerial vehicle has to be released from the vehicle to allow the vehicle to be removed from the landing pad, leaving the retaining medium attached to the capture surface. The shoes must then be removed from the landing pad, such as by peeling the shoes from the capture surface, and new engagement components must be attached to the landing elements prior to each flight. Another drawback is that system is not suitable for aerial vehicles that are so heavy that the engagement components would be crushed. A further drawback is that the area of the landing pad is determined by the size of the landing gear of the aerial vehicle, which must contact the pad at all points.
As a consequence, in light of the above drawbacks, there is a need of a landing arresting system for VTOL aerial vehicles that allow for a fully automated operations cycle, whereby the aerial vehicle can be repeatedly launched, retrieved, serviced and re-launched, without manual intervention at any point, that is suitable for both lightweight and heavy VTOL aerial vehicles and whose landing and take-off platform is not determined by the size of the landing elements.